1. Technical Field
This invention relates to a versatile washing apparatus, and more particularly to a self-contained and portable, fully integrated washing and drying system for washing large quantities of a wide range of articles such as pallets, totes, containers, dunnage and other like structures through the controlled application of a high pressure wash fluid, along with the removal of the excess moisture from the article.
2. Discussion
Articles such as pallets, totes, containers, trays, dunnage trays and other like structures are used in a wide variety of applications in many industries to transport quantities of various items. In the food industry such items may include produce, meats, fruits, vegetables and dairy products. Such articles are also used extensively in factories to help transport industrial parts from one work area to another or between plants or from a factory to a warehouse or end user.
As can be appreciated, such articles as pallets, totes and containers often become dirty, especially with repeated use. In the food industry this can be particularly troubling if such articles are exposed to, for example, leaking milk cartons, fruit juice cartons, etc., and then reused without proper cleaning. The reuse of such articles can result in the contamination or damage to the product being transported. As can be appreciated, keeping articles such as pallets, totes, containers and other like structures clean and free from bacteria and odors is therefore particularly important in the food industry. It is also important in other factory settings to maintain such structures clean so that one or more dirty pallets, totes or trays do not transfer dirt and contaminants and potentially damage the product being transported.
Pallets, totes and other like structures often have ribbings and complexly shaped surfaces adapted to hold a wide variety of parts and an assortment of products. Often, the surfaces of such structures include a plurality of recesses, and in some instances very deep cavities, which are difficult, slow and tedious to clean and dry by hand. In many applications, where literally hundreds or thousands of pallets are used, cleaning such pallets by hand, such as with a hand-held spray system, is much too time consuming and not cost effective considering the time that is often required to clean and dry just a single pallet adequately.
In response to the above need to quickly and easily clean large numbers of pallets, totes and other like articles, a number of attempts have been made to provide various forms of apparatuses in an attempt to clean large numbers of such articles quickly, easily and efficiently in an automated fashion. However, previously developed apparatuses designed for cleaning such articles have suffered from a number of drawbacks. One such attempt at providing an automated pallet cleaning apparatus is disclosed in U.S. Pat. No. 5,446,942 to Whitehorn. The apparatus of this patent, however, requires the use of steam as the cleaning agent, together with a large boiler for producing the steam needed in a cleaning operation. As will be appreciated, the use of a steam generator for supplying heated steam requires a certain time for building up pressure and heat. When a large number of pallets or other like articles are to be cleaned, feeding one such article after another through the apparatus does not allow sufficient time to generate the heated steam, and the cleaning must be halted for a period of time to allow the boiler to regenerate the desired pressure. Thus the throughput of the apparatus is limited and may not be sufficient in applications where it is desired to clean hundreds or thousands of pallets or like articles at a time. The use of a large boiler also requires a large amount of power from a standard service, must be permanently located within the plant, is expensive and time consuming to install, is costly to operate and requires extensive maintenance. Also, most importantly, the boiler of the device disclosed in U.S. Pat. No. 5,446,942 calls for only 100 lbs. of pressure, and the steam alone provides no impingement force onto the surface of the article. The steam also generates significant moisture and humidity into the plant, which can cause corrosion and other harmful side effects within the plant's environment.
Other prior art pallet washing devices have relied on the application of heated liquid, such as the apparatus disclosed in U.S. Pat. No. 5,372,153 to Dobson. This patent discloses a pallet washing apparatus having a number of fixed spray nozzles and a heater for supplying heated fluid to the fixed spray nozzles. As will be appreciated, this device also requires a significant amount of electrical power for heating the cleaning fluid. If a boiler is used to heat the washing fluid the same shortcomings described in the Whitehorn U.S. Pat. No. 5,446,942 patent will apply. Obviously, if the apparatus has been powered off for some time, when it is first powered back on some length of time will be required to allow the cleaning fluid to be heated to the necessary temperature before the apparatus can be used. Also, this apparatus requires a constant supply of fresh water, which means it must be permanently located and connected to a fresh water supply. Also, since the fluid needs to be heated before use, only a limited number of pallets or other like articles are able to be cleaned before the fluid holding tank needs to be recharged and the fluid therein heated to a sufficient temperature before an additional quantity of pallets can be cleaned. Thus, the throughput of this apparatus, and virtually all other apparatuses requiring a heated fluid, is severely diminished because of the need to heat the fluid to a sufficient temperature before applying same to the pallet or other article being cleaned. Also, this patent does not address a means to dispose of the contaminants removed from the articles and merely puts the contaminants and contaminated fluid down a drain, which would likely not be allowed by current environmental regulations. Also, the fixed nozzles defined in the patent may not provide an adequate spray pattern for articles of varying sizes and shapes, and may not effectively clean a variety of different articles such as pallets, totes and dunnage. Finally, this patent provides no means to dry the article or remove the excess moisture, which would restrict the articles or pallets from being stacked or put back into service until they are air dried.
Previously developed apparatuses for washing pallets and other like articles have also suffered from one or more other drawbacks or disadvantages. One such disadvantage is the lack of portability. Often, such as in factories, it would be much easier to transport the pallet washing apparatus to a specific area of a plant or factory rather than transporting hundreds or thousands of pallets to the apparatus, as is often required. Other pallet and tote cleaning apparatuses are generally not readily portable. This is especially so with apparatuses that require a heated fluid source, and therefore require a large electrical service and permanent electrical and water connections. These systems present significant maintenance procedures and require specialized training and knowledge to operate. Any apparatus requiring such a large service and permanent connections will generally be very large and restricted to one part of a building, plant or factory where such service and connections are available. These systems take up a large area of valuable floor space and often require special plumbing, venting, water treatment and other special accommodations to the plant facilities. These systems are generally made for one specific type of article and have no versatility to clean a variety of different articles or shapes. They also generally clean through submersion and part agitation, clean with heavy solvents and chemicals, require extensive washing and rinsing chambers, and are limited in throughput capacity.
Another drawback of many pallet and tote cleaning apparatuses is the need for a permanent, constant or periodic supply of fresh water as well as the need for a drain for disposing the contaminant entrained water. The need for permanent or frequent access to a water supply to frequently recharge a water container of the apparatus, as well as the need for frequent access to a drain, can severely limit the use of such a cleaning apparatus within a facility.
Yet another problem presented by many previously developed apparatuses for cleaning pallets and totes is the lack of a collection system for collecting and filtering the contaminant-entrained wash fluid before such fluid is drained. For environmental reasons, it is undesirable to simply drain the contaminant-entrained wash fluid from the apparatus without some form of filtering process which removes contaminants which might be harmful to the environment.
Perhaps the most significant drawback, however, with previously developed pallet, tote and container washing apparatuses is the inability to completely clean the surfaces of such articles. As explained above, the surfaces of pallets, containers and totes are often complexly shaped with numerous recesses, pockets, etc., which are often difficult to clean with a spray system having fixed spray nozzles with limited spray coverage and/or a spray system of only a limited pressure, and little impingement force. With some previously developed apparatuses, it has been necessary to spray down various areas of a pallet or like structure with a hand held spray wand after the pallet has passed through the apparatus for cleaning. Spraying with a hand-held wand has often been necessary to reach the various recesses, grooves, pockets, etc. in such articles effectively. As explained above, however, manual spraying with a hand-held wand is very time intensive, adds significantly to the overall cost of cleaning, and is subject to operator error, judgement and has no consistency of cleaning.
It is therefore a principal object of the present invention to provide a versatile apparatus for quickly and efficiently cleaning and drying articles such as pallets, totes, containers and other like structures automatically, and with a minimal degree of operator intervention.
It is still a further object of the present invention to provide an apparatus for washing pallets, totes, containers and other like structures quickly and easily with the use of a wash fluid delivered under high pressure from a spray system incorporating a plurality of spray nozzles, and where two or more of the spray nozzles are rotated at relatively high speeds, which cause a plurality of high pressure jet streams to impact every square inch of the surface of the article to be cleaned a multiple number of times and provide a knife-like cleaning action, and which further does not require the wash fluid to be heated.
It is a further object of the present invention to provide effective cleaning through a plurality of high pressure fluid jet streams to blast off dirt and contaminants without the use of scrubbing brushes or other mechanical devices.
It is still another object of the present invention to provide an apparatus for washing pallets, totes, containers and other like articles which incorporates a closed-loop water reclamation system for filtering contaminant-entrained wash fluid, filtering the wash fluid and resupplying the wash fluid to a container for reuse, such that a continuous, external supply source of water and a water drain are not necessary to the operation of the apparatus once the container of the apparatus has been charged or filled with a predetermined quantity of water. Such features would permit the apparatus to be used in various areas of a factory, plant, warehouse, etc. where a fresh water supply and a drain are not available.
It is still another object of the present invention to provide an apparatus for washing pallets, totes and other like articles which has a very high throughput capacity for cleaning very large numbers of such articles in a limited amount of time.
It is a further object of the present invention to provide a "turn key" system that merely needs a simple garden hose connection to a water line and a standard 240 volt service electrical connection for operation.
It is a further object of the present invention to have a completely versatile system that is able to clean and dry a wide range of different products of varying sizes and configurations with only simple mechanical adjustments being required to portions of the apparatus.
It is a further object of the present invention to provide a means to thoroughly dry and remove the majority of moisture from pallets, totes and other like articles as they exit a washing chamber of the invention.